


Upsie Downsie

by FreddyFazbutt



Category: Undertale (Video Game)
Genre: Additional Warnings In Author's Note, Author knows what they're doing, Biting, Blood Kink, Burping, Chara might make an appearance, Dom Frisk, Everybody is suspicious but Frisk is too smart to get caught, Explicit Fetish Content, Explicit Sexual Content, F/M, Female Frisk, Forced Relationship, Forced Soul Bonding, Frisk bullies Sans sexually, Frisk calls Sans Sansy, Frisk does what she wants to Sans, Frisk has huge tits and a huge ass, Frisk is not innocent, Frisk swears a great deal, Humiliation, Kidnapping, Kink Exploration, Licking, Manipulative Frisk, Nipple Licking, POV Frisk, POV Sans, Please comment tell me what you think, Poor Sans, Post-Undertale Pacifist Route, Sans Has a Bad Time, Sans Needs A Hug, Sans gets shrunk by Frisk, Sans has a tiny dick, Sans is being forced into it, Sans is going to get fucked by a giant teen girl, Seriously if you come here looking for dominant Sans you're looking in the wrong spot, Sexual Abuse, Sexy Times, Size Difference, Size Kink, Sub Sans, Teasing, Teen Frisk, The Author Regrets Nothing, This is NOT Bittybones, This is not recommended for Sans lovers, This is the opposite of all those dom Sans stories out there, This isn't mindless porn, Those two go hand in hand, Tiny Sans, Underage Sex, Unhealthy Relationships, Vore, sexy frisk
Language: English
Status: In-Progress
Published: 2017-06-27
Updated: 2017-06-27
Packaged: 2018-11-19 12:45:23
Rating: Explicit
Warnings: Graphic Depictions Of Violence, Rape/Non-Con, Underage
Chapters: 4
Words: 2,628
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11313675
Author URL: https://archiveofourown.org/users/FreddyFazbutt/pseuds/FreddyFazbutt
Summary: After a pacifist route Frisk bullies Sans into unpleasant situations sexually. However when Sans tries to tell anyone they don't believe him and he has to try to survive the might of one giant teen girl and her hormones.





	1. The bullying begins

**Author's Note:**

  * Translation into 日本語 available: [アップシーズンダウンシーズン](https://archiveofourown.org/works/14129370) by [FriendlyFlower](https://archiveofourown.org/users/FriendlyFlower/pseuds/FriendlyFlower)



> One last warning for you Sans lovers turn back now if you don't want to see Sans fall apart and get wrecked by Frisk. I'm going to tear him apart. =)

You were at home in bed masturbating to a picture of an anime girl when you realized how much fun you could have with Sans he could be like your little plaything.  You got up from your bed and called him "Sans?" He replied "Yeah Kiddo"

You asked "Why don't you come over?" He said "Sure" You giggled as you waited. You heard the knock and opened the door to see Sans standing there and said "Hi Sans I've got something to show you"

You led him into your room where you handed him a drink of water mixed with shrinking powder that you got from somewhere and said "Look at me!" You wore your usual purple and blue sweater with shorts as he said "You look nice" as he took a drink and said "This water tastes pretty good" so he drank it all.

He said "What is it you wanted to show me?" A poof and suddenly he was screaming as he was falling. He was the size of a ant as you put your hand out and caught him. He said "What the fuck Frisk?" You said "Silly Sansy you're mine to play with forever"

He gulped as he asked "What are you going to do to me?" Your smile grew as you took off your sweater then your shorts leaving you in your underwear. You then said "Remove your clothes Sansy" he said "but you are only 15!" You growled and said "Do it or i'll eat you"

Sans undressed and he turned blue as you poked his tiny blue dick. he said "D-Don't" You laughed and said "This is your dick? i have a bigger dick than you and i don't have one" he said "D-don't m-make fun of me"

You undressed all the way and said "Ok little Sansy time for you to enter my dungeon" you went and laid on your bed with your pussy exposed. You set Sans on your belly and said "Jump in"

He jumped into your vagina and once he was inside he began rubbing the walls of your pussy making you moan out in pleasure. You began rubbing your nipples causing you to moan even more and your juices to began building up.

You felt Sans stop rubbing and asked "Can I come out now?" You sighed and said "Fine Sansy but you can lick my nipples now" he climbed out of your pussy and walkled over to your tits and began licking them.

The pleasure ran across your body like a chill and you moaned louder as Sans magic tongue made it's way up and down on your right tit. You said "Fuck yeah good job my little Sansy"  and you were about to orgasm.

He began licking your nipples harder until finally a stream of cum flowed freely from your vagina and flowed across your mid section. You sat up not bothering to wash yourself off and noticing the tiny blue liquid flowing onto Sans bones.

You said "Ooh Sansy's first orgasm I'm so proud" He said "Why did you do this to me"

You said "Because I fucking felt like it I was fucking horny and I wanted some Sans in my vagina don't worry Sansy I'm not going to keep you here I'm going to let you go" He asked "You are? You nodded with a sexy look on your face.

You said "But it's been fun teasing you and having you inside me so I will be having more later" Sans smile dropped as he said "What? aren't you going to restore me?"

You said "Sure" and snapped your fingers restoring him to his original size and he tried to attack you but his magic deflected off you and onto him. He said "What?"

You showed your soul which was now connected to his and said "I bound you to my soul so I can control your magic and size" He asked "When did you do that?"

You giggled and said "You are an idiot when humans and monsters have sex for the first time the dominant one of them takes control of the other's soul I'm dominant so i got control"

Sans said "Fuck I can't help but have sex with you now" You giggled and said "Have fun suffering from lack of me" and pushed him out the door. Toriel came in and said "Did you hang out with Sans Frisk"

You were covered by the door and Toriel could only see your head as you said "Yes but I'm going to go to bed Mom see you tomorrow" and you rushed into your room then laid on your bed still naked.


	2. Burpy Frisk

**Summary for the Chapter:**

> A gassy Frisk teases Sans and burping ensues.

**Notes for the Chapter:**

> Things are about to get very burpy in here

You were still lying on your bed naked when there was a knock on the door. You said "Fuck" and quickly redressed before Toriel came in and asked "My child would you like to have this case of pop?"

Toriel had a case of your favorite pop Root Beer so you said "Most definitely thanks Mom" She said "Your welcome Mettaton gave these to me but I don't drink pop" You nodded as Toriel left the room and you cracked open a pop.

Before long you'd drunk half the case when you fell asleep. The next morning your phone rang from your nightstand as you picked it up and asked "What the fuck is it Undyne?" Undyne said "You sound tired punk but want to play some video games with Sans and Papyrus?"

You said "Sure let me ask Mom" and went downstairs where Toriel was cooking breakfast and asked "Can I go over to Sans and Papyruses house to play video games?" Toriel nodded and you called Undyne back and said "I'll be right over".

So thats why you found yourself at Sans and Papyruses house. You knocked and Sans opened the door to look a little shocked as you said "Sup Sansy" He asked "Are you going to fuck me already please don't bro's here?"

You said "No bonehead but I think i'll shrink you for a little bit tell them you went to Grillby's" and you held your hand out as it pulsed blue and  Sans shrunk to the size of a dust speck. You picked him up and were about to say something when you let out a "URRRP"

Your root beer breath blasted Sans like a wave and he said "Gross what'd you drink" You giggled and said "Just half a case of root beer" and said "You've given me a good idea"

You used Sans magic to suspend him in your throat so he'd feel the full frontal force of your burps. You then went inside where Papyrus and Undyne were playing Little Big Planet 3 on Papyruses PS4 and let out another "URRRRP" Undyne said "Holy Asgore punk thats quite the burp"

You could feel Sans disgust from the burp and said "I got a free case of root beer last night" and sat down on the couch. Papyrus said "WHERE'D SANS GO?" You burped again "UURP" and said "He went to Grillby's" and you were handed a controller.

For the next hour you continued to burp nonstop and torture Sans. Finally it was time for you to go home and you let out your biggest burp yet "URRRRRRRRRRP!!!!!!!!!!!!!!!!!!!!!!"

Undyne gave you a high five and said "Whoa Punk that was the biggest burp I've ever heard see you later" You said goodbye and closed the door. You then opened your mouth and asked "Did you enjoy that Sansy? he said "If I say yes will you let me out of here?"

You said "sure" before letting out a "URRRRRRP!" and Sans said "Thats so gross Frisk" and you said "It gives me satisfaction to humilate you like this" and took him out of your mouth.

You grew him back and he said "At least you didn't actually eat me" You smiled and said "Not yet" and left him to be covered in root beer breath smell and your saliva.


	3. Nippy Sans

**Summary for the Chapter:**

> You reveal one of your kinks to Sans and apply it during your second sex.

**Notes for the Chapter:**

> I can't believe how many views this has gotten guess i'm not the only who hungers for something like this.

You were at home now and you were relaxing when your phone rang you groaned and answered it "Sansy what the fuck?" "Frisk are you done with me can i be free?" You laughed and said "Nope your mine forever"

He said "But Frisk I think Toriel wants to marry me" You said "WHAT?" He said "she was coming onto me earlier today after you left" You growled and said "Then I think i want you to come over I've got a plan"

Sans said "But aren't you happy for me and Toriel? You laughed darkly and said "Get. Over. Here. Now" you went outside to wait.

Two minutes later Sans pulled up and parked then got out of the car asking "What is it? you used the bond to shrink Sans to the size of a doll and bent down to say "My plan is to mark you for my own" and held out your hand which Sans took.

You led into your house breathing a sigh of relief that Toriel wasn't here. You led Sans into your bedroom and said "I have a blood kink" Sans asked "What is that?" You smiled and said "Bite me" and Sans opened his jaws but hesitated and said "Isn't this going to hurt?"

You smiled and shook your head as Sans teeth came down and opened a tiny wound which was bleeding. You moaned as you said "lick the blood off my wound" so Sans used his tongue to slowly lick the blood that was flowing from your wound.

You moaned louder and your juices began building up as Sans licked it more and more then you said "Heal it" Sans used his magic to heal your wound as you ripped off yoùr sweater and shorts leaving you in your underwear.

You said i'm going to bite your dick softly so it leaves a mark so get undressed" Sans said "WHAT?" You said "Sansy just do it" he undressed and you picked up his tiny dick and slowly and gently bit down on it.

The mark left over on his dick spewed a little dust which you licked moaning louder now. Sans moaned as you licked it. You slipped your underwear off and said "Fuck I'm never going to get tired of this"

You then said "Sans i want you to bite my left tit" He said "Okay" and climbed onto you then bit your left tit. You screamed out in pleasure as your pain turned into pleasure.

He then began licking it which made you scream even more until WHOOSH a wave of cum blasted out of your vagina mixing with the blood pouring down and forming a gigantic river of blood and cum.

You said "Heal me up and get down there and give it a lick" he said "Ok" and healed your wound then he slid down beside the river of blood and cum. You said "Actually i've got a better idea" and used the bond until the river was like an ocean to him.

You giggled and said "Go swimming" and he went into the river swimming in your cum and blood until there was a knock on the door and you said "Shit well at least I orgasmed" and quickly picked up Sans then set him on the floor making him bigger again.

You said "Lick the rest of this off me" Sans bent down and licked the rest of the blood and cum off your vagina. you then quickly got dressed and shrunk Sans until he was doll sized again then stuck him in your shorts pocket.

You answered the door and it was Alphys who said "Sorry to bother you Frisk but Papyrus is looking for Sans and he asked me to look for him and his car is here"

You felt Sans moving in your pocket and said "Yeah Sans is here but he's hanging out with me" Alphys said "Oh okay Papyrus will understand that"

You breathed a sigh of relief as you set Sans on the ground making him normal size and saying "Papyrus I hadn't even thought he would be suspicious oh well" and you let Sans go home. Then you walked back into your room and jumped on the bed tired so you fell asleep.


	4. A fun afternoon

**Summary for the Chapter:**

> You and Asgore garden together. Later you tease Sans with your stinky feet.

The next day you sat up in bed when you heard a knock on your door. You were still in your clothes from yesterday as you got out of bed and answered the door. It was Asgore who said "Howdy Frisk"

You gave him the Toriel look as sweat appeared on his forehead. He asked "uhh are you busy today?" Your scrutinizing look was replaced with a smile as you said "No why?" Asgore asked "I was wondering if you'd like to help me garden?" You said "Sure" and Asgore drove you over to his house.

At his house you and him talked as you helped him weed his garden and plant some tulips. He asked "So how's Tori-Toriel doing?" You said "Good she doesn't grumble about you anymore"

His face turned hopeful as he asked "Do you think she'd let me see her?" You thought for a moment then said "Actually I think she misses you" You thought back to a few months ago when she had stopped grumbling about Asgore.

You had just gotten home on the last day of school when you were about to walk into her room to say hi but you didn't hear anything like you usually did because around this time she would grumble about Asgore.

But when you went in her room she seemed happy like she was thinking about him. You had went to your room to ponder and now in this moment Asgore's face lit up like a christmas tree but you said "Whoa whoa there romeo let me find out for sure"

He nodded as you finished planting the seeds. Later you were at home again when your phone rang when you answered it Sans asked "So you want to see a movie?" You asked "And that would be where?"

He said "At my house of course Paps is spending the night at Undyne's house" You said "Sure Sansy I've got stinky feet so hope your ready for that" Later that night you stood at Sans front door as you knocked wearing your blue and purple striped pjs.

He opened the door and said "You're planning on sleeping over aren't you?" You said "Fuck yeah" and he led you into his living room. You used the bond to shrink him to the size of a child then said "You are going to be my footstool"

He set the movie up and you placed your bare stinky feet on him as he said "Oh god Frisk why do your feet smell so bad?" You giggled and said "I did gardening with Asgore today" Sans said "Disgusting" you then wiggled your toes making him cough it was so bad.

Throughout the entire movie you tortured him with your horrible foot smell until finally it was the credits. You took your feet off Sans head and said "That was fun Sansy time for bed" and you shrunk him to the size of ant.

You bent down and picked up tiny Sans then said "So you get a prize for being such a good boy" and you went up to his room where you placed him on the bed then turned around and wiggled your bum slowly as you laid your ass on Sans tiny body.

You said "I'm probably going to fart just so you know" there was a muffled noise as you laid down and fell asleep letting out a "Pffffff!" as you fell asleep.

**Works inspired by this one:**

  * [Undyne's Sealed Fate](https://archiveofourown.org/works/15536478) by [FriendlyFlower](https://archiveofourown.org/users/FriendlyFlower/pseuds/FriendlyFlower)




End file.
